Python/ctypes: handle string conversion for graph interface property.
Python/ctypes: handle string conversion for graph interface property.

radarsat1/libmapper,radarsat1/libmapper,libmapper/libmapper,libmapper/libmapper,malloch/libmapper,radarsat1/libmapper,libmapper/libmapper,malloch/libmapper,malloch/libmapper,libmapper/libmapper,malloch/libmapper,radarsat1/libmapper,malloch/libmapper,radarsat1/libmapper,libmapper/libmapper,libmapper/libmapper,malloch/libmapper